The reduction of atmospheric emissions is considered to be one of the major trends of the first decade of the new millennium. All over the world industry is looking for products being more environmental save, liberating less volatiles and showing improved biodegradability. This is particular true for those areas of application needing high working temperatures, as for example road construction. Temperatures of typically 150° C. and above are necessary to allow the binders in the asphalt or bitumen compositions to become viscous enough in order to coat the particles completely. It is of course desirous to work at lower temperatures since this saves energy costs and reduces the unwanted emission from burning fuel, fumes and odours generated at the plant and paving site.
From the state of the art several technologies are known allowing the reduction of temperature in the treatment of asphalt and bitumen compositions by using special “low-temperature binders”. For example, WO 2004/108830 A1 (SMAC) suggests to use certain hydrocarbon waxes, while U.S. Pat. No. 4,242,143 B2 (Elf) discloses for the same purpose polyolefins and US 2003/0231928 A1 (Sasol) paraffins obtained from the Fischer-Tropsch synthesis.
Therefore it has been the object of the present invention to develop new auxiliary agents for asphalt, bitumen or bitumen emulsions, especially for application in road construction, providing binders with excellent coating performance even at temperatures of about 100 to 120° C.